The Last Dredging And Port Construction Magazine, The End Of An Era

The last issue of Dredging and Port Construction
The last issue of Dredging and Port Construction

It is not very often that one experiences the end of an era. Hiroshima, the fall of the Berlin Wall, Brexit. Those were very important events with a global impact. Now there is another end of a period, with only a limited impact on a small community affected. After half a century, our trusted journal ‘Dredging and Port Construction’ has come to an end1. In the fast moving media world, this will only be a footnote in history. Yet, as a magazine, it was close to our community. It reported on projects and people we knew, but also as a platform for the CEDA to communicate with us for 42 years2.

IHS Markit has decided to cease this publication, the lack of new subscriptions and decreasing advertisements. You know, the general malaise in paper printing. Somehow, the digital revolution didn’t turn out so well for them. Other digital media providers covering the dredging industry seem to have a better business model to survive the transition. Right?

Well, there is a big disadvantage of those free service, hot shot, social media savvy new comers, they just forward press releases that they receive or sweep up from social media. They don’t have dredging literate expert editors writing long genuine articles about topics that would not have access to coverage by themselves. Having your own knowledgeable editors doing original research vetting the facts and reporting from a broad perspective with a solidly founded opinion is expensive. And that makes it very difficult for a classic publisher to survive in these modern times.

We will suffer in this new era without our trusted DPC. We can sign up to the usual free subscription daily newsletters from the new media publishers and read the endlessly repeating press releases. We will miss the in depth reports on big projects or critical comments on regulatory issues. We will have to figure this out from within our own social media bubbles. It will narrow our view and I certainly hope we don’t lose the perspective of other members in our community.

Please be advised, that also the website will be closed at the end of June3, leaving only the digital archive of the magazine accessible4, which goes back to May 2015. Although the last editor, Ines Nastali, told me she is happy to send out articles if requested by the dredging community. There will only be some dusty old paper versions that are stored in a forgotten archive or that one issue we keep for some sweet memory. At least that is what I have done. Over the years, I have written several articles that have been placed in this magazine and I cherish those issues. The first one was already long ago about a CEDA excursion to the IJsseloog in the Ketelmeer project. The last one was a reprint from my post5 about energy transition in the dredging industry discussed during the CEDA Dredging Days6.

CEDA Dredging Days 2019 panel discussion (Credit: CEDA)
CEDA Dredging Days 2019 panel discussion (Credit: CEDA)

It was a good experience to contribute to the magazine that way. And made me proud, that my posts at this website were picked up by the media. I will see what will come along in the future. I am open to any opportunity. At least, I am determined to keep www.discoverdredging.com alive as an independent platform to point out dredging related topics. And this will be a lonely place left to find an opinion about our community, albeit, very personal.

Although we are an industry in an economic sense, it is a community. When I think of companies and projects, I think about the people I know over there. And my memory about Dredging and Port Construction will not only be the magazine, but also the nice cooperation with the editors. At this moment I would like to especially thank Tony Slinn, Lisa Maher and Ines Nastali for a their work.

Ines Nastali, senior custom publishing editor (Credit: Ines Nastali)
Ines Nastali, senior custom publishing editor (Credit: Ines Nastali)

References

  1. End of an era, IHS Markit DPC
  2. IHS DPC Latest, CEDA
  3. About us, IHS Markit DPC
  4. Welcome to your digital magazine portal, IHS Markit
  5. We Choose To Adopt Energy Transition, But How Will We Succeed? Discover Dredging
  6. Dredging industry addresses energy transition challenges, IHS Markit DPC

See also

CEDA

Graduation Of Carsten Markus: Designing And Casting Of Impellers

Impeller under operating load.
Impeller under operating load.

Last week, Carsten Markus graduated on his assignment with our research department Damen Dredging Equipment. He investigated the alloys that are used to cast our impellers and the responses of the materials under operating conditions. We are always improving our dredge pumps and Carsten’s work has been a great contribution for our development.

For every dredging application, the material for the dredge pump parts can be carefully selected according the specific requirements on the sediment handled. Off course, one would like to have the hardest, most erosion resistant material available. Less erosion is less wear and a longer lifetime1.

Wear part material hardness in relation to wear index

However, there is a downside to choosing very hard material: it will be very brittle also2. Basically, the ultimate tensile stress coincides with the yield stress. There is no reserve for the load. When the stress surpasses the yield strength, it just snaps. Conversely, a tough material has a lot of reserve. After deformation beyond the yield stress, the load can still increase without a catastrophic failure. Usually, the stresses would not be that high, the thickness of the wear parts is dimensioned for erosion reserves and thick parts have low stresses. The high stresses can come from concentrations. Either when the wear reserves are eroded, or when a heavy load is concentrated on a very small area. Usually stones. Stones are a very common problem in a dredging project. So, next to the hardness of an alloy, also the toughness will be a very important characteristic. And toughness is related to the yield elongation after failure.

For the various materials you would like to know how the base load relates to the tensile stress. This would be an indication whether there is reserve in the elastic region to accommodate the impact of an occasional stone. This base load depends on many factors in the pumping process. Mainly the pressure generation in the mixture over the blades. Most known literature is about the force distribution in the volute of the pump, as this is directly related to the radial forces and consequently the bearing and shaft calculations. The CFD simulations in this graduation project revealed the skewed load on the volute and consequently the load variations on the impeller.

Transient CFD simulation of a dredge pump. The rotation appears wrong , but is correct (Wagon-wheel effect).

As emphasised before, it is very beneficial to operate your dredge system around the Best Efficiency Point (BEP). Not only the shaft and bearings suffer less, also the impact of the stresses and their variations in the impeller are less. If the operating point differs from the required capacity, the BEP can be moved by changing the dredge pump speed. As long as head requirements permit the adjustment.

Radial load as a function of pump characteristics.
Radial load as a function of pump characteristics.

As a result of Carsten’s research, we were able to improve our operating load models for the whole dredge pump and gained insight into the material responses to these. Thank you Carsten.

Due to the measures taken for the containment of the Corona virus, the graduation itself and the party to celebrate it, where done remotely over internet. Let’s enjoy the real beer later, after all this commotion is over. Stay home, stay safe.

Carsten’s graduation defence session under Covid-19 measures.
Carsten’s graduation defence session under Covid-19 measures.

References

  1. Do You Have Wear Parts For Spare?, Discover Dredging
  2. Brittleness, Wikipedia

See also

We Choose To Adopt Energy Transition, But How Will We Succeed?

President John F. Kennedy speaking at Rice University on September 12, 1962 (Credit: NASA)
President John F. Kennedy speaking at Rice University on September 12, 1962 (Credit: NASA)

‘We choose to go to the moon.’ Was the famous speech at Rice University of President John F. Kennedy to express his ambition to send his nation to the Moon1. At the time, his call was far from clearly achievable. But it was a very clear roadmap and it quickly gained traction. The success of the Apollo project is well known. Neil Armstrong did land on the Moon within a decade and the American flag is still planted on its surface.

Panel discussion at the CEDA Dredging Days 2019 with Mike van der Vijver
Panel discussion at the CEDA Dredging Days 2019 with Mike van der Vijver

At the CEDA Dredging Days 20192, there was an interesting panel discussion on ‘Energy transition: the views in our dredging community’3. Panel members were: Eric de Deckere, Michael Deruyk, Kaj Portin and Klaas Visser. The discussion was moderated by Mike van der Vijver from MindMeeting. As an introductory teaser to the audience, he posited the claim: ‘Excessive ambition drives breakthroughs’. The question is: ‘Is the dredging industry ambitious enough to convert to a new fossil free energy source?’ The audience was polled for their opinion on a scale from one to ten and the response ranged from three to eight. The three represented the position, that the industry is not doing much. What is visibly done, are only single purpose, company specific solutions that are not adopted by the community. On the other hand, there was also a very positive signal with an eight for ambition. The sense of urgency is very well present in the community. Most companies are developing plans and cooperating in working groups, such as the CEDA Working Group on Energy Efficiency4. Also, the government is pitching in with initiatives on zero emission maintenance dredging, where the dredging community is actively participating in putting forward proposals.

So, why is there still no zero emission dredge? What is the ambition lacking? The hint is the opinion that the effort is not focussed. The strong motivation in Kennedy’s speech was that there was a very clear picture what to do. What do we do: ‘Put a man on the Moon’. When: ‘By the end of the decade’. How: ‘Bring him safely back’. Ambition with a clear plan can indeed achieve great things. Ambition without motivation will only bring daydreaming and lethargy.

Block diagram of influencers for energy transition in the dredging community
Block diagram of influencers for energy transition in the dredging community

To achieve something, we need motivation. And who is responsible for pulling this off? Mike polled the audience again for: 1) Government, 2) Public opinion, 3) Companies, 4) Technology. There was not a clear picture here either. All positions are valid. Another driver is the reward for the effort. The Apollo project effectively created part of our modern society. What would the energy transition yield for the dredging community: ‘Learning by challenge’, ‘Flexibility and resilience in energy generation’, ‘Low maintenance and higher independence’?

At this website I can’t change the world, but addressing most issues mentioned, I can only put forward my idea on the ‘How’ motivation. We know how to apply power. As long as the power arrives electrically, we can use it. Essentially, we have to generate electricity with a flexible power source. The investment lifetime of a dredge often exceeds 30 years, but under the current circumstances, the power plant only lasts ten. The solution would be to have some separate module for power generation. Either locally, near the dredge, or remote at the end of the pipeline. As every project and application will be different, it will be a challenge to design the specific solution. But I am looking forward in developing the solutions below with any interested customer5.

Transition schedule to convert to fossil fuel free dredging equipment
Transition schedule to convert to fossil fuel free dredging equipment

References

  1. We choose to go to the Moon, Wikipedia
  2. CEDA Dredging Days 2019, CEDA
  3. Programme 7 November 2019, Panel Discussion, CEDA
  4. CEDA Working Group on Energy Efficiency, CEDA
  5. Innovation at Damen Dredging Equipment, Damen

See also